"Groups Perform Better Than the Best Individuals on Letters-to-Numbers Problems: Effects of Group Size", Patrick Laughlin, Erin Hatch, Jonathan Silver, and Lee Boh, University of Illinois at Urbana Champaign; Journal of Personality and Social Psychology, Vol. 90, No. 4

Thanks to Wes, who got word of this APA press release on NPR! Great study! I specially like the type of task they used and how it was able to uncover the use of problem-solving strategies of different complexity levels. Here is the APA release which includes a link to the original paper: http://www.apa.org/releases/group042306.html